NAS ext4 drives initialized with Win10 Computer manager :( guid parttable and ext4 filesystem loss

uyjjhak · 04-20-2021, 01:03 PM

Hello,

TL;DR
1. Some ext4 filesystems on different drives was initiated in Windows 10 disk manager
2. Currently there is no ext4 partitons and I suppose the partition table was overwritten by Windows - currently I see GUID Partition Table and only small (abt 100MB) Microsoft Resevred partition on the begginning of the 10TB drive.

3. After that I do not tried any writing/changing tools, only scanning it by rstudio, dmde and testdisk without seeing the proper partitions
4. There is about 10 hdds affected on that problem, I have connected it to the HBA or Motherboard Sata controller.
5. I don't have backed up that before

From many years I am building home NAS from different old parts.
So, with 4th gen i5 CPU, ATX board and 4 SATA controllers I am having fun with keeping lot of wasting about 60TB space on different disks.
So, the current config is:
4xWD GOLD 10TB
4xWD GOLD 14TB
2xWD RED 6TB (old mdadm raid0)
2xWD RED 6TB (old, 2nd, mdadm raid0)
On each of that drives, before using only under Ubuntu, I have done mkfs.ext4 /dev/sda or /dev/md0 for example.
That was full config, rest of usage of this was through the SMB and NFS shares over the LAN. On this hardware I never had started Windows before.

And last days I have had to start computer with Windows 10 to make MB bios update. I have installed all drivers, and later I have go to the Computer management/Storage and next... I have clicked "initialize disks". I am fully sure that the problem had started then. For better understanding - I am writing about this dialog which I have completed without thinking.
https://www.windowscentral.com/sites...windows-10.jpg
As that was over the night and I am sure that I have clicked it for all on my ext4-formatted disks. These filesystems doesn't appeared under windows ofc.
So, after clicking on that I can saw the drives with "unknown" partition but even then I hadn't saw what I've had done...

Of course from that time I haven't had any changes in files or structure these drives.

Today I started my hardware with Ubuntu, like always. And.... what freezed me - I saw that all of my hard disks, which was visible in Windows before - currently are partitioned GUID partition table and has only one, about 100MB partition named "Microsoft Reserved".
And now... Maybe I am in biggest problem in my life. So, all of my ext4 filesystems created directly on block device are gone.

Previously I don't made paritions, just creating filesystems on device:

Code:

mkfs.ext4 /dev/sdb

for example.

As lastly I have many problems with raid devices I also have bought R-studio and DMDE apps which I am trying to use.
But on R-studio I don't see any well styled filesystem and list of files which would be covered only by another type of partitioning. There is a mess with files, directiories, inodes.
DMDE has had not finished scanning the drive yet, but as I checkced testdisk (without seeing the proper disk partitions) on another device I am affraid that also it could has a problem.

OMG... what can I do in that situation ?

Yes, I know, make a backup before. But I don't have backed up everything as currently I am trying to reorganize that. That was the reason of using of faster and safest WD GOLD drives to easier organize large photo assets, and almost everything from my digital life...

Emerson · 04-20-2021, 02:35 PM

Filesystem directly on sdb, I'd start with 'file -s /dev/sdb' and see what it tells me. Then I'd try and force mounting it as ext4, with 'ro,noload' - these options make sure even journal is not written. Then go from there, if it tells you there is a healthy superblock then use it to mount your drive and the data should become accessible, minus sectors which were overwritten by Windows.

uyjjhak · 04-20-2021, 03:15 PM

Quote:

Originally Posted by Emerson

Filesystem directly on sdb, I'd start with 'file -s /dev/sdb' and see what it tells me. Then I'd try and force mounting it as ext4, with 'ro,noload' - these options make sure even journal is not written. Then go from there, if it tells you there is a healthy superblock then use it to mount your drive and the data should become accessible, minus sectors which were overwritten by Windows.

Thank you, unfortunately that doesn't work:

Code:

root@ubu-4690:~# mount -t ext4 -o ro,noload /dev/sde /mnt/
mount: /mnt: wrong fs type, bad option, bad superblock on /dev/sde, missing codepage or helper program, or other error.
root@ubu-4690:~# file -s /dev/sde

/dev/sde: DOS/MBR boot sector MS-MBR Windows 7 english at offset 0x163 "Invalid partition table" at offset 0x17b "Error loading operating system" at offset 0x19a "Missing operating system"; partition 1 : ID=0xee, start-CHS (0x0,0,2), end-CHS (0x178,254,63), startsector 1, 4294967295 sectors
root@ubu-4690:~#

Emerson · 04-20-2021, 03:53 PM

I thought you just need help to get started? Here is the next step.

syg00 · 04-20-2021, 06:32 PM

Where to start ...

If you originally created the raid devices and filesystems directly on the device nodes themselves, you destroyed all the meta-data when you let Win10 reformat them. All of it - hence the mess of files you mentioned. I haven't purchased R-Studio, but from their website it looks like it should be a good tool to use.
Typically it is a matter of scouring the files and trying to recreate the filenames if you consider that important. For photos the exif usually has enough to do the job. For text maybe grep will give you some hints - Office files need unzipping first. Just a lot of legwork, and you won't get it all done by scripts.